i have a d15b7 with a t3. rc 310cc, my fuel pressure regulator has been replaced, so has my fuel filter. i notice that after i start my car the aem uego goes rich like 12.5 and the more the car warms up the more it starts to lean out until it just girks and bucks because of being so lean. It really starts doing it after i do a good pull of 7psi, no cel or anything the car will idle just fine at 675rpm's. my spark is all fine and my plugs are gaped to .030.

the car started doing it like 4 months ago and has just started getting really bad. I barrowed a fuel pressure gauge from work and hooked it up when i started the car it read 36psi on the gauge so i taped it to my window and drove around, i did a pull and it started dropping until i got home it was at a 31psi. now my fuel pump is stock along with the motor thats in the car and has 187,000 miles on it. Honda recommends 40psi. i am looking at purchasing a walbro 255

please help

 

what heat range are your plugs and what are u using for management?... pick up some bkr7e ngks from autozone those are what i ran in my turbo civic at 12psi on a afc hack setup..

if u dotn have a fmu(rising rate regulator) or something in there for management there is your problem..

also when running cold the car WILL run richer.. its how EFI cars are tuned from the factory..theya re also programmed to compensate.. so the car compensates to run the 310cc injectors at X pressure with whatever vaccum/boost level it sees most.. that is why a honda ecu can idle a 700cc injector with no management.. but it wont be able to utilize it correctly through the driving range. so running around out of boost it will try to reduce the duty cycle a bit to keep the engine running. but when u slam into it and reach boost.. it cannot correct for that much air induced under the same settings..

hence either raising Fuel pressure under boost or increasing injector duty cycle under boost.. u can also retard timing underboost.. all of which need to be triggered in some way in relation to boost level. '
on a side note i ran closer to 12:1 and 11.8:1 AFR on my car too it was safer and made more power 12.5:1 is rich for an NA setup but is kinda on the lean side when going forced induction. however that was your reading out of boost if i read correctly which would mean your car is loading up on gas when not in boost..

anyway since u didnt really explain stuff that really mattered in your fuel system its hard to diagnose what it is.